Justification:
The species is listed as Critically Endangered. All available information indicates that the species is in a clear and protracted decline throughout its small range due to intense hunting pressure, accelerated by continued fragmentation of its habitat to increased human access (mainly through road construction). No part of the species' extent of occurrence is effectively protected from hunting. Local hunters in the species' range commonly go years without seeing an animal, indicating very low and suppressed population density. Threats from hunting are exacerbated by other factors including loss of habitat. The new Ho Chi Minh Road through the Annamite Mountains in Viet Nam, (with additional roads branching to Lao PDR) is a major and probably unmitigatable threat. Rates of decline are likely to increase rather than decrease, and a population reduction of 80% over three generations is estimated for the past, present and future (=A2cd+3cd+4cd). The remaining population is estimated at Pseudoryx conference convened in Viet Nam in 2004 (Hardcastle et al. 2004).

This species occurs only in the Annamite Mountains of Viet Nam and the Lao Peoples' Democratic Republic (Lao PDR) (Grubb 2005). Most records are from south of the Song Ca River in Viet Nam, although a population to the north has also been found (Dung et al. 1994, Kemp et al. 1997).

In Lao PDR, records come from as far west as central Bolikhamxay Province. Suitable habitat is, or was, probably more abundant in Viet Nam than in Lao PDR, but Viet Nam's much higher human population density has severely reduced both habitat and Saola numbers in the habitat that remains. In Lao PDR there is evidence of occurrence in Bolikhamxay, Khammouan, Savannakhet and Xekong Provinces; it probably also occurs in southern Xieng Khouang Province. In Viet Nam there is evidence of occurrence in Nghe An, Ha Tinh, Quang Binh, Quang Tri, Thua-Thien Hue and Quang Nam Provinces. It is suspected to occur in less than 15 forest blocks in the two countries.

The area of forest remaining in the known historical range of the Saola is 5,000 to 15,000 sq. km, but much of this range is probably no longer inhabited by the species. The number of Saola subpopulations - defined as those in non-contiguous blocks of habitat - is probably in the order of 6 to 15, and none likely number more than 50 animals. Consequently, total Saola population is undoubtedly less than 750, but is likely much less.

No formal surveys have been undertaken to estimate Saola numbers accurately (Tham Ngoc Diep et al. 2004). Accurate population estimates would be exceedingly difficult to obtain due to the secretive nature of the taxon, the difficulty in making direct observations in dense forest habitat - a difficulty compounded by the species' rarity - the rugged terrain, and the remoteness of much of its habitat. Furthermore, one of the two range governments, Lao PDR, has often withheld permission to conduct detailed studies of the species in its territory. Nonetheless, it is known that subpopulations are small, highly localised, and isolated.

To date, scientists have categorically documented Saola in the wild on only four occasions. In fact, there is not yet a reliable method for detecting the species other than direct observation or camera trapping. Incidences of either of these encounters are extremely rare. The first photograph of a Saola in the wild was taken in 1998 from a camera trap set near a mineral spring in Pu Mat National Park, Viet Nam (Whitfield 1998). A few months later the species was camera-trapped in Lao PDR, in Bolikhamxay Province (Robichaud 1999). The only other potentially reliable method of detection is through genetic analysis of feces.

The paucity of data on Saola is itself an indication of its critically small population. Though populations of other ungulates in the Saola's range are severely depressed, they are seen far more commonly by local inhabitants than is the Saola. Recorded sightings of these ungulates occur at a frequency often two orders of magnitude higher than for the Saola. Documented villager sightings of Saola in the past decade don't number in the thousands or hundreds, but in the tens. In contrast, sightings by villagers of muntjacs, pigs and even Sambar are so common that researchers generally don't quantify them.

Analysis of hunter interviews conducted in In Pu Mat National Park, Viet Nam in 1998 and 1999 estimated that about 18 Saola survived in the Khe Bong area in the southeast of the reserve and about eight in the Khe Chat and Khe Choang areas in the center. In 2003, research suggested that these numbers had been reduced by about 50% over the intervening five years, despite the best efforts of the forest authorities and other responsible agencies (Weir and Dinh Van Cuong 2004).

Speculative population estimates of 70 to 700 in Lao PDR and several hundred in Viet Nam were provided in the IUCN Antelope Action Plan (Mallon and Eames 2001, Timmins 2001). Subsequent surveys in Lao PDR indicated that the current population there is likely near the country's low estimate, i.e., fewer than 100 remaining (Robichaud and Timmins, 2004). It is unlikely that Saola's total global population is greater than the low hundreds at most (i.e., fewer than 250 mature individuals). Such a total estimate was made in the 1990s, based on the known range and reports from hunters (Dung et al. 1993, Schaller and Rabinowitz 1995). The situation has deteriorated considerably since then. The surviving population is highly dispersed and its fragmentation is worsening. Saola numbers may be so low that no viable populations remain.

The species occurs in the northern and central Ammanites, in climatically wet evergreen forest (Duckworth et al. 1999, Lunde et al. 2004), and is present only in forest blocks over approximately 25 square kilometers (R. Timmins pers. comm.2006). The habitat preference appears to be highly specific, namely evergreen forests with little or no dry season. Saola have been found in high quality, dense forest. Whether or not it can inhabit other types of wet forest is not known. It may associate with areas close to forested streams (Dung et al. 1993). Thus, many areas within the presumed range in both Lao PDR and Viet Nam are not suitable due to the predominance of forests with pronounced dry seasons, limestone forests, etc.

The altitude range of the Saola is uncertain. While it seems to be a mid-low elevation species, most of the forest below 400 m within its presumed range has been lost and a high proportion of the remaining forest is over 1,000 m. There is no indication that the species occurs above 1,200 m.

Information from villagers in its range indicates that Saola are mainly solitary, although there are some reports of groups of two or three animals, and rarely groups as large as six or seven (Dung et al. 1994). The species is possibly territorial, and might mark territory with scent from its large maxillary gland.

Single foetus pregnancy has been documented. Information from local villagers suggests this to be the norm (Robichaud 1998). Saola may have a fixed breeding season with births occurring in the summer.

Captive Saola exhibited primarily diurnal, or diurnal and crepuscular, activity; however, it is not known if this is typical under natural conditions (Robichaud 1998). Local reports suggest Saola is a browser, feeding mostly on leaves (Dung et al. 1994).

While tropical forests have inherently low ungulate biomass, natural Saola densities are probably even lower than other sympatric ungulates such as wild pigs, Sambar, and muntjacs. This is due in part to the presumed lower reproductive output, solitary nature, and likely larger territory and/or home range of the Saola as compared to some of these other ungulates. It is clear that Saola populations must also be unnaturally depressed, as populations of all wild animals larger than 20 kg in its range have been significantly reduced by human exploitation. Field survey encounter rates with muntjacs and pigs in the Saola's range are remarkably low compared to other areas in Asia, and wild cattle, elephants, and tigers are all nearing extinction in its range (e.g., Duckworth and Hedges 1998). Even typically resilient species such as Sambar are scarce. The declines are corroborated by local villagers across the area, who consistently report major reductions from former abundances.

The greatest threat to Saola is hunting. While wildlife in the Saola's range are most threatened by the traditional medicine trade, specific demand for Saola is almost non-existent as the species is unknown in the traditional Chinese pharmacopoeia. Instead, the animal is snared incidentally in the intense, general pursuit of other species for the medicine and bushmeat trade.

Local subsistence hunting also takes a toll. Saola may be particularly susceptible to being hunted with dogs (Robichaud 1998). The intensity of hunting in the Saola's range is hard to adequately describe, but some figures hint at the enormity of the problem. The human population of Viet Nam is more than 70 million, that of China more than a billion. Together, they comprise an enormous market for wildlife products. For example, tens of millions of wild turtles are imported, legally and illegally, into China annually (van Dijk et al. 2000 and papers therein).

The bushmeat trade is more localized, but it is estimated that eight million Viet Namese, i.e., eight million people with the propensity to eat wildlife, live within 100 km of forest inhabited by Saola. It is unlikely that any Saola occur more than 35 km from a village. The pressure from proximal human settlements is so intense that there are no longer core areas in the Saola's range not regularly reached by hunters. Every square kilometre of Viet Namese and Lao forest within Saola range probably has snares capable of capturing Saola set in it every year. Intensity in some areas probably reaches many thousands of snare-nights per square kilometre per year.

Habitat destruction is also a threat to the Saola, forests in their range being cleared for small-scale agricultural use, timber extractions, roads, and hydropower development. However, there continues to be more Saola habitat than there are Saola.

Presumably, the generation time of Saola is greater than three years, and reproductive output is lower than that of muntjacs, Southern Serow or Sambar, putting Saola at a conservation disadvantage. Additionally, pigs, Southern Serow, muntjacs and Sambar retain significant population reservoirs in areas of lower hunting pressure, such as difficult to reach areas of habitats such as dry evergreen forest that are not amenable to Saola. The absence of Saola from such habitats is either an indication of a greatly accelerated rate of decline as compared with other species or an ecological intolerance, neither of which bodes well for the species.

Finally, the bushmeat trade has little likelihood of abating as long as there are pigs, muntjacs, and civets to be hunted, but Saola will become extinct long before these more common species are hunted out. In Viet Nam, informal interviews with hunters in Pu Huong Nature Reserve revealed that 30 Saola were killed there between 1995 and 2003 (Hoang Xuan Quang and Cat Tien Trung 2004). In some local villages in Viet Nam, hunters used to kill three individuals per year 10 years ago, but now rarely catch any (Do Tuoc, Alexei Abramov pers. comm. 2006). Most hunted specimens have been killed in winter (at least in Viet Nam), when Saola are in more accessible lowland habitats (Dung et al. 1994).

Snaring is less intensive in Lao PDR, but there the majority of Saola range lies along the Viet Nam border, and is heavily poached by Viet Namese, and/or coincides with the distribution of the ethnic Hmong in Lao PDR, who avidly and effectively hunt a wide range of wildlife, including Saola. These forests are as nearly devoid of large mammals as forests in Viet Nam.

Economic development and expanding wealth in the region are likely increasing rather than decreasing the demand for wildlife medicines and bushmeat. Development projects in the region commonly cite poverty as a principal cause of biodiversity loss, but the main threat in the Saola's range, at least for the mid-term, is increasing wealth in its range countries and in China. Wealth, not poverty, is the principal driver of the wildlife trade.

The recent construction through the Annamite Mountains in Viet Nam of the Ho Chi Minh Road, parallel to and with branches to the Lao border, is a severe and probably unmitigatable new threat. It directly affects Saola subpopulations by forest fragmentation and increased human access for hunting and forest clearance in several critical areas.

Saola have proved difficult (thus far impossible) to maintain in captivity (Robichaud 1998). Approximately 20 Saola, at least, have been captured in Viet Nam and Lao PDR, and all died shortly afterwards, with exception of two released back into the wild (Stone 2006).

Protected area management has been largely ineffective in the Saola's range and existing and new protected areas offer little hope for conservation of the species. Protected areas have proved particularly impotent in the control of poaching or as a mechanism to safeguard areas from economic development. Protected areas in the region are commonly the site of hydropower projects, road construction, and mining. As yet there has been no demonstration of effective anti-hunting measures in any area in the range of Saola, nor are any likely to become effective within the next five years, at best.

Although specific trade demand for Saola has been low, it could be increasing as the species grows rarer. In 2000, horns marketed as belonging to the rare Saola were offered for sale in Hanoi, Viet Nam for US$600 (Alexei Abramov pers. comm. 2006).

Human population growth in the Saola's range is high, both from births and in-migration, which will intensify the threats to the species.

Efforts to initiate Saola conservation activities in Lao PDR have received little government support, and in some cases have been actively blocked. The reasons for this are not clear, but may be due to fear of slowing logging and hydropower development.

In summary, intense hunting and a multitude of exacerbating pressures on Saola are increasing and evidence indicates that the species, which is naturally uncommon and localized, is in a major decline. The trend is likely to result in the extinction of Saola in the foreseeable future.

This species is listed on CITES Appendix I and both of its range countries are CITES signatories. It is protected by national law in Viet Nam (Decree 48; IB) and in Lao PDR (Ministry of Agriculture and Forestry Regulation 360).

In Lao PDR Saola are probably still found in Nakai-Nam Theun and Xe Xap National Protected Areas, and in Nam Chat-Nam Pan Provincial Protected Area. However, only Nakai-Nam Theun has active, well-funded management. Saola occur in several forest blocks outside protected areas - in fact, its range in Lao PDR outside protected areas may be nearly as large as its range within, and perhaps larger. In Viet Nam it is probably found in Vu Quang and Pu Mat National Parks; Pu Huong, Phong Dien and Dak Rong Nature Reserves and the proposed Bac Huong Hoa Nature Reserve. A new protected area for the species has been proposed in Thua-Thien Hue and Quang Nam Provinces.

Two editions of a conservation action plan for the species in Lao PDR have been written (Robichaud 1997, 1999), but permission for implementation has not been granted by the Lao government. Recommendations from a 2004 Saola workshop held in Viet Nam (Hardcastle et al. 2004) included updating and implementing the 1999 Lao Action Plan and preparation of a comprehensive Saola Conservation Action Plan for Viet Nam. The latter has now been drafted.

Highest, immediate priorities for both countries are increased patrolling against snaring and other types of hunting.

Hassanin, A. and Douzery, E. J. P. 1999. Evolutionary affinities of the enigmatic Saola (Pseudoryx nghetinhensis) in the context of the molecular phylogeny of Bovidae. Proceedings of the Royal Society of London B Biological Sciences 266: 893-900.